Recording thermometers are used for the protection of shippers and receivers of perishable goods as a guard over the temperature environment during transit. Various types of thermographs are employed and which are loaded and activated by the shipper and subsequently unloaded by either the receiver or a laboratory to which the instrument must be sent for analytical reporting. Needless to say, time is of the essence in receiving perishable goods on consignment, and subsequent analysis offered days late is of little real value; while the loading and handling of the instrument by unskilled persons results in malfunctions. For example, such instruments are often operated by spring motors which may be inadvertantly left unwound, or the chart inadvertantly left disconnected from drive mechanism.
The in-transit shipment of such an instrument has for its primary purpose the function of monitoring the environmental temperature condition of the shipping compartment of a carrier, the said instrument being installed or packed with the goods to be protected thereby. Thus, the thermograph operation is highly advantageous to the shipper and receiver by providing a record of temperature relates to time which is within the supervision of the carrier. However, the shipper and/or receiver cannot safely delegate operation of such an instrument to the carrier inasmuch as the assurance of a proper shipping environment cannot be entrusted to the person who is ultimately liable in the event of his irresponsibility. In practice, such instruments are deliberately tampered with by allegedly unknown persons, and obviously so for the purpose of destroying a probable incriminating recording; thereby shifting responsibility to the shipper, for example, in the event of damaged goods delivered to the receiver, when in reality the unproven fault lies with the carrier. The problem involves the seriousness of business transactions involving substantial money investments, and it is a general object of this invention to improve the business relations between shipper, carrier and receiver by eliminating doubt as to environmental temperature intransit, and all of which is beneficial to all concerned by indicating whether or not the intransit temperature was properly maintained.
Heretofore, instruments of the type under consideration have been weighty and difficult to handle, the mechanism thereof have been over engineered and merely an aggregation of the functions involved. For example, chart transferring means have been powered by drive means governed by a time piece, spring wound for activation or switch controlled for electrical operation, and all housed within a casing. In the interest of protection, the casing completely encases the instrument so that the temperature change must penetrate therethrough and which does take time. However, the time duration of a temperature condition is of the essence, and a time lag in its recordation should not be tolerated. Furthermore, prior art instruments that are so encased are also protectively housed within containers which add to the temperature isolation and time delay in recordation. In other words, the prior art instruments for this purpose rely upon heat absorption through weighty structure and are extremely slow to respond. Therefore, it is an object of this invention to directly expose the thermometer to the surrounding air temperature, and to simultaneously incorporate all the encasement and protective features into one shipping container which is also the housing and/or physical body of the instrument, with the thermometer per se directly exposed to the surrounding environment.
The loading and handling of prior art thermograms is a field problem to the shipper who must rely upon inexperienced personnel. Reference is made to the written information which is to be applied to the chart in order to associate it with the goods and the instrument into which it must then be loaded. It is this association which must be accomplished at the moment of departure, it being an object of this invention to provide a pre-loaded instrument in which the chart has been installed and a portion thereof exposed upon a table for receiving scribed or written information associating the factors involved in the shipment. Heretofore, verifying copies of information so placed upon the chart at the moment of departure have not been available, and it is an object therefore to provide a manifold through which a person can write upon a prepared form which establishes the required associated information. The manifold copies are then available to the shipper, carrier, receiver and to the instrument laboratory responsible for its operation and maintenance.
The starting of the prior art thermographs has involved the winding of spring motors of the operation of switches as by means of special mountings; all of which is directed to avoiding reliance upon personnel but not at all fool proof. For examples; the person loading the thermograph will forget to wind it, or the person mounting the thermograph will neglect to set it properly in its mounting. Therefore, it is an object of this invention to provide a temperature recording thermometer, a thermograph, that is self-energized by the most fundamental and simplified act of pulling a release pin, which may then be discarded, and in no case will its replacement cancel the "start." Thus, manual winding or the operation of control switches is eliminated, and there is no reliance upon complicated mountings that control operation.
The in-transit sealing of thermographs for the purpose of rendering them tamper proof has not been altogether satisfactory, since the characteristic solid and heavy closed structures thereof do not entirely eliminate tampering. For example, knowledgeable persons who wish to disturb operation of such instruments find ways to secretly enter sufficiently to destroy the the production of a reliable thermogram. It is, therefore, an object of this invention to provide a seal that is so related to the closure of the instrument container that its undamaged condition is a warranty that no attempt at entry was made. With the present invention, the container is a folded box wherein there are no through passages to the interior when associated with the instrument frame which it supports. Any attempt to insert an instrument therethrough is readily detectible, especially when such damage is externally visible upon a freshly applied container as is required when practicing this invention.
The determination of operation has been a problem with prior art thermographs, from the standpoint of removing the thermogram therefrom, and stopping the drive mechanism thereof, and in re-shipping of the instrument to its source of supply. Removal of the thermogram normally requires partial disassembly while stopping of the drive is not always attempted, and while re-shipping usually entails a separate container which may or may not have been preserved by the carrier. As to drive operation, usually a clock movement, return in the mails or by any public carrier raises the question of its being a timed explosive device. Therefore, it is an object to provide a thermograph from which the thermogram is extractible without dismanteling in any sense, merely by cutting a paper seal and by opening a lid, the thermogram being exposed for its then obvious mode of extraction. Cooperatively with the foregoing objective it is also an object to utilize extraction of the thermogram as the motivating function operating to automatically deactivate the drive means that transported the chart during the shipment of goods. It is still another object of this invention to incorporate a reshipment seal which remains intact with the instrument container during its utilitarian period as a thermograph, and which is available to be conditioned and used to reseal the instrument within its container-housing for reshipment to its source for subsequent re-establishment as a pre-loaded instrument.
Further, it is an object to provide a preloaded and easily operated thermograph of the character thus far referred to, which is economical in all of its aspects of manufacture, distribution, use and return for re-cycled distribution, etc. With the present invention, the fewest number of static and dynamic parts are fully integrated and so combined to perform their correlated functions with assurance of results, and the resulting lightness in weight coupled with the suspension of the instrument frame within the container-housing provides for protective shock resistance.